Issue with DEC modifier and 18F26K83

[Andy Wood]

Hi,

When using the DEC modifier with HSEROUT on this MCU I am having some issues. If I run the code below, the serial output is:

Testbyte=

[Andy Wood]

I'll try again... something went wrong with the post formatting..

Hi,

When using the DEC modifier with HSEROUT on this MCU I am having some issues. If I run the code below, the serial output is (without the quotes):

"Testbyte=

[Andy Wood]

My post keeps getting truncated... not sure what is going on..


When using the DEC modifier with HSEROUT on this MCU I am having some issues. If I run the code below, the serial output is:

Testbyte=

[Andy Wood]

There must be something in the text that is upsetting the forum formatting.... Let's try again....

When using the DEC modifier with HSEROUT on this MCU I am having some issues. If I run the code below, the serial output is:

See attached image

If the HSEROUT line is changed to hserout ["Testbyte= ",testbyte,10,13] the serial output is:

Testbyte= 2

which is expected.

Not sure what is going on.

Code has been copied and pasted directly from MicroCode Studio Plus and some of the formatting has been lost (i.e. capitalization of directives). Compiler version is PBPX 3.1.1.4


DEFINE OSC 64

DEFINE HSER_RXREG PORTC
DEFINE HSER_RXBIT 7
DEFINE HSER_TXREG PORTC
DEFINE HSER_TXBIT 6
DEFINE HSER_BAUD 115200

clear
Testbyte var byte

TRISA = %00000000 '
TRISB = %00001000 '
TRISC = %10000000 '

testbyte = 50

main:

hserout ["Testbyte= ",testbyte,10,13]
pause 200
goto main

[Charles Leo]

Do I understand correctly that with the DEC modifier, it doesn't output "50"?

You aren't using defines for RCSTA and TXSTA. Have you checked the bit-timing with an oscilloscope?

What is in play on the receiving side? (Serial Communicator, HyperTerminal, TeraTerm, etc.) Have you tried something different there?

I have the chip for testing, but it will take me a while to set it up.

[DavidP]

Andy, Try this:
hserout ["Testbyte= ",DEC testbyte,10,13]

I also notice that you are sending a "50" value to the serial port and it is un-formatted. If the receiving side was working correctly it would print a character "2".

Also judging by the remainder of the received message I would suspect a baud rate issue. Possibly on the receiving side.

Try lowering the baud rate and give it another try.

[Andy Wood]

Thank for the replies so far.

Charles - you are correct. When using the DEC modifier it does not output "50". If I remove the DEC modifier the output is ASCII "2", which of course is 50 decimal.

I have added defines for RCSTA and TXSTA - no change.

I have reduced the baud rate to 9600 - no change.

Initially I was using Serial Communicator to receive the data. I have also checked the output using RealTerm and it is the same.

By way of background, I have been using this exact hardware to transmit and receive CAN packets at 250 kBit/s with no issue. As part of this setup, HSEROUT was used as below with the HEX2 modifier at 115200 baud and it works as expected:

HSEROUT [HEX2 PGN1,HEX2 PGN2," ",HEX2 RXB0D0," ",HEX2 RXB0D1," ",HEX2 RXB0D2," ",HEX2 RXB0D3," ",HEX2 RXB0D4," ",HEX2 RXB0D5," ",HEX2 RXB0D6," ",HEX2 RXB0D7,10,13]

Because of the above, I do not believe there is a problem with the hardware or bit timings etc.

I had to post the output from Serial Communicator as an image - one of the control codes in the string must upsetting the online forum formatting as it kept truncating my posts at that point.

My full test code is below:

 #CONFIG
    CONFIG FEXTOSC = HS        ;HS (crystal oscillator) above 8 MHz; PFM set to high power
    CONFIG RSTOSC = EXTOSC_4PLL        ;EXTOSC with 4x PLL, with EXTOSC operating per FEXTOSC bits
    CONFIG CLKOUTEN = OFF        ;CLKOUT function is disabled
    CONFIG PR1WAY = OFF        ;PRLOCK bit can be set and cleared repeatedly
    CONFIG CSWEN = ON        ;Writing to NOSC and NDIV is allowed
    CONFIG FCMEN = OFF        ;Fail-Safe Clock Monitor disabled
    CONFIG MCLRE = EXTMCLR        ;If LVP = 0, MCLR pin is MCLR; If LVP = 1, RE3 pin function is MCLR
    CONFIG PWRTS = PWRT_64        ;PWRT set at 64ms
    CONFIG MVECEN = OFF        ;Interrupt contoller does not use vector table to prioritze interrupts
    CONFIG IVT1WAY = OFF        ;IVTLOCK bit can be cleared and set repeatedly
    CONFIG LPBOREN = OFF        ;ULPBOR disabled
    CONFIG BOREN = ON        ;Brown-out Reset enabled according to SBOREN
    CONFIG BORV = VBOR_245        ;Brown-out Reset Voltage (VBOR) set to 2.45V
    CONFIG ZCD = OFF        ;ZCD disabled. ZCD can be enabled by setting the ZCDSEN bit of ZCDCON
    CONFIG PPS1WAY = OFF        ;PPSLOCK bit can be set and cleared repeatedly (subject to the unlock sequence)
    CONFIG STVREN = ON        ;Stack full/underflow will cause Reset
    CONFIG DEBUG = OFF        ;Background debugger disabled
    CONFIG XINST = OFF        ;Extended Instruction Set and Indexed Addressing Mode disabled
    CONFIG WDTCPS = WDTCPS_31        ;Divider ratio 1:65536; software control of WDTPS
    CONFIG WDTE = OFF        ;WDT Disabled; SWDTEN is ignored
    CONFIG WDTCWS = WDTCWS_7        ;window always open (100%); software control; keyed access not required
    CONFIG WDTCCS = LFINTOSC        ;WDT reference clock is the 31.0 kHz LFINTOSC
    CONFIG BBSIZE = BBSIZE_512        ;Boot Block size is 512 words
    CONFIG BBEN = OFF        ;Boot block disabled
    CONFIG SAFEN = OFF        ;SAF disabled
    CONFIG WRTAPP = OFF        ;Application Block not write protected
    CONFIG WRTB = OFF        ;Configuration registers (300000-30000Bh) not write-protected
    CONFIG WRTC = OFF        ;Boot Block (000000-0007FFh) not write-protected
    CONFIG WRTD = OFF        ;Data EEPROM not write-protected
    CONFIG WRTSAF = OFF        ;SAF not Write Protected
    CONFIG LVP = OFF        ;HV on MCLR/VPP must be used for programming
    CONFIG CP = OFF        ;PFM and Data EEPROM code protection disabled
  #ENDCONFIG


DEFINE OSC 64

DEFINE HSER_RXREG PORTC
DEFINE HSER_RXBIT 7
DEFINE HSER_TXREG PORTC
DEFINE HSER_TXBIT 6
DEFINE HSER_BAUD 9600 

DEFINE HSER_RCSTA 90h
DEFINE HSER_TXSTA 20h

    clear
    Testbyte  var byte

    TRISA =  %00000000    '
    TRISB =  %00001000    '
    TRISC =  %10000000  '

    testbyte = 50

main:    

    hserout ["Testbyte= ",dec testbyte,10,13]
    pause 200
    goto main

[Henrik Olsson]

Andy,
Instead of using DEC, can you try:

hserout ["Testbyte= ", #testbyte,10,13]

I seem to remember an issue with DEC vs # but I could've sworn it was # that didn't work while DEC did. I don't know what the internal differences are compiling your code for a 18F26K80* produces significantly smaller .hex when using # so SOMETHING is different and perhaps # works for your current needs while Charles figures out why DEC doesn't.

Or I'm just way off target :-)

* I'm still on 3.1.0.4 here so can't compile for K83 devices.

/Henrik.

[Andy Wood]

Hi Henrik,

I tried your suggestion and hre is the result:

Testbyte= 11

[Andy Wood]

Hi Henrik,

Some of the extended characters have been stripped from my previous reply. I have attached the result as an image.

[Henrik Olsson]

Strange, but OK, it was worth a try I guess.
I'm afraid I'll have to leave this one to Charles then. I'd be interested in knowing what the problem turns out to be.

/Henrik.

[DavidP]

Good catch Henrik, I forgot all about that problem from the past.

[mpgmike]

To use the "#" method you must first create a place to put the result. I use the ARRAYWRITE command that parses the individual digits of the value ("5" and "0" in this case) into the array:

ARRAYWRITE HhDcA, [#HhDc]

where my variable ("50" for example) is in HhDc and my array is HhDcA[3]. Then I can send out the ASCii digits one at a time:

DO
        LOOP UNTIL U1FIFO.5 = 1             ;Wait until TXREG is empty
    U1TXB = HhDcA[0]
    DO
        LOOP UNTIL U1FIFO.5 = 1             ;Wait until TXREG is empty
    U1TXB = HhDcA[1]
    DO
        LOOP UNTIL U1FIFO.5 = 1             ;Wait until TXREG is empty
    U1TXB = HhDcA[2]
    DO
        LOOP UNTIL U1FIFO.5 = 1             ;Wait until TXREG is empty

(The above code is for a PIC18F47K42)

[DavidP]

Wow Mike, One byte at a time? That will for sure slow down the program flow. Why not use interrupts to do the USART function? Then you can do something like this:

'*********************************************************************
SNDCHAR: 'INCREMENT BUFFER POINTERS
'*********************************************************************
TX_OUTPUT = TX_OUTPUT + 1
TX_OUTPUT = TX_OUTPUT & OUTSIZE
TX_DAVAIL = TX_DAVAIL + 1
IF PIE1.4 = OFF_ THEN
@ INT_ENABLE TX_INT ; ENable TX UART Interrupts
ENDIF
IF TX_DAVAIL > FIVESIXTH THEN 'if buffer is more than 5/6th full allow buffer to empty (I usually use 64 for the buffer size)
WHILE TX_DAVAIL > ONESIXTH 'allow buffer to empty to 1/6th then continue.
PATDOG = ON_ 'FEED THE DOG
WEND
ENDIF
RETURN

'*********************************************************************
SERIALOUT: 'OUTPUT SERIAL STRING TO PORT 1
'*********************************************************************
BYTEIN = 0
WHILE OUTARRAY [BYTEIN]
TX_BYTES(TX_OUTPUT) = OUTARRAY(BYTEIN)
BYTEIN = BYTEIN + 1
GOSUB SNDCHAR 'INCREMENT BUFFER POINTERS
WEND
RETURN
'*********************************************************************

And in the main program loop you do something like this: It makes sending formatted strings extremely easy.

ARRAYWRITE OUTARRAY,["CALCULATED GAIN & OFFSET:",DEC5 SLOPE,",",DEC5 OFFSET,10,13,0]:GOSUB SERIALOUT

[mpgmike]

That works also. Sometimes the code has the luxury of spending time with a function, and other times too much is happening at any given time. I wanted to show the mechanics of a process more than the most efficient method.